Ake Sellstrom (L), head of the chemical weapons team working in Syria, hands a report on the August 21, 2013 Al-Ghouta massacre to United Nations Secretary-General Ban Ki-moon in New York, in this handout picture provided by the United Nations September 15, 2013. REUTERS/Paulo Filgueiras/UN Photo/Handout via Reuters (UNITED STATES – Tags: POLITICS CONFLICT CIVIL UNREST) ATTENTION EDITORS – THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT IS DISTRIBUTED, EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS